Repair or waterproofing laminates are known in the art. A typical laminate is comprised of a flexible sheet-like permeable or semipermeable support in face-to-face contact with a sheet-like bituminous mastic. These materials are used to repair, waterproof, strengthen or otherwise improve roads, roofs, building foundations, bridge decks, parking decks and the like. As repair materials they can be applied directly to the cracked or weakened areas of any given substrate (i.e. road, concrete surface, roof, etc.). The laminates can also be used during construction to reduce the need for subsequent repair and to otherwise improve the quality of the project. A wide range of other applications for such laminates is known to those persons of skill in the art.
The repair or waterproofing laminates to which this invention pertains are characterized by an extended mastic construction. This means that the bituminous mastic extends beyond at least one end of the support. An extended mastic construction is illustrated in FIG. 1.
FIG. 1 shows a side view of a sheet-like permeable or semipermeable support 1 in face-to-face contact with a bituminous mastic 2. The face-to-face contact occurs at the support-mastic interface 3. Note that a portion 4 of the mastic 2 extends beyond the edge or end of the support 1. This extension 4 of mastic represents an extended mastic construction.
The extended mastic construction is useful when one strip of repair or waterproofing laminate is partially overlapped by another strip of the material. The extended mastic construction allows for a mastic-to-mastic contact between the strips. FIG. 2 illustrates this overlapping of strips.
FIG. 2 shows two strips of the repair or waterproofing laminate applied to a substrate 5 (e.g. road, concrete surface, roof, etc.). Note that both mastics 2 are in contact with substrate 5. The extended portion of the mastic of the strip furthermost to the left is in contact with the mastic of the other strip. This mastic-to-mastic contact occurs at the interface 6. The mastic-to-mastic contact provides a watertight joint or seal.
The bituminous mastic 2 is, by design, very "sticky". This presents problems and difficulty with respect to storing, transporting and handling of the laminate. For this reason release papers are used to cover the exposed portions of the mastic (i.e. those portions not covered by the support 1). Each release paper is treated with silicone on the face of the paper in contact with the mastic 2. FIG. 3 illustrates the positions of the release papers. Release paper 7 covers the entire face of the mastic 2. Note that this particular face of the mastic is not the face of the mastic in contact with the support 1 but rather is the reverse face. Release paper 7 is called the primary release paper. Release paper 8, which is typically a narrow strip, covers the extended portion 4 of the mastic 2. Note that release paper 8 and support 1 are in contact with the same face of the mastic 2. Release paper 8 covers that portion of the mastic face not covered by the support 1. Release paper 8 is referred to as the secondary release paper.
With the release papers in place the strip of repair or waterproofing laminate can be rolled up and unrolled without interference from the "sticky" mastic. In practice rolls of the laminate are transported to the repair or construction site. The release papers are carefully removed on site as the laminate is applied to the substrate (i.e. road, concrete surface, roof, etc.). Removal of the secondary release paper requires an extra handling step. Once the secondary release paper is removed the exposed mastic can be dirtied or cause handling and disposal problems. Occasionally removal of the secondary release paper causes removal of some of the mastic.